Bis(dicyanamido-κN)[tris(3-aminopropyl)amine-κ4 N]nickel(II)

In the title complex, [Ni(C2N3)2(C9H24N4)], the NiII atom is coordinated in a distorted octahedral geometry by one tris(3-aminopropyl)amine (trisapa) ligand and two dicyanamide (dca) ligands [one of them disordered in a 0.681 (19):0319 (19) ratio]. Intermolecular N—H⋯N hydrogen bonds involving the N atoms of the dca anions and the trisapa amine H atoms result in the formation of a three-dimensional network.

In the title complex, [Ni(C 2 N 3 ) 2 (C 9 H 24 N 4 )], the Ni II atom is coordinated in a distorted octahedral geometry by one tris(3aminopropyl)amine (trisapa) ligand and two dicyanamide (dca) ligands [one of them disordered in a 0.681 (19):0319 (19) ratio]. Intermolecular N-HÁ Á ÁN hydrogen bonds involving the N atoms of the dca anions and the trisapa amine H atoms result in the formation of a three-dimensional network.   Table 1 Hydrogen-bond geometry (Å , ).
transition metal dicyanamide complexes display long-range magnetic ordering, with the nature of the ordering dependent on the particular metal ion involved. Thus the Cr (47 K) and Mn (16 K) compounds are antiferromagnets (Manson et al., 1999), while the Co (9 K) and Ni systems (21 K) are ferromagents (Batten et al., 1998). It is well known that the structure and the magnetic property of the complexes are related to the nature of the co-ligands (Ghosh et al., 2011;Mastropietro et al., 2013;Ion et al., 2013). Although a great effort is focused on studies of dicyanamide complexes with multidentate schiff bases (Sadhukhan et al., 2011;Fondo et al., 2011;Bhar et al., 2011), few dicyanamide complexes with polyamines as co-ligands have been reported recently (Khan et al., 2011). To further study the effect of the nature of co-ligands on the structures and properties of dicyanamide complexes, we herein report the synthesis and crystal structure of the title new nickel dicyanamide complex [Ni(trisapa)(C 2 N 3 ) 2 ] (I).
The nickel ion in I is coordinated by four N atoms from the tris(3-aminopropyl) amine and two terminal N atoms from two dicyanamide anions to form a distorted octahedral geometry, in which the equatorial plane is formed by the three N atoms(N2, N3, N4) of tris(3-aminopropyl)amine and one nitrile N atom (N8) of a monodentate (disordered) dicyanamide, where the disorder atoms are C12 and C12′, N9 and N9′, C13 and C13′ respectively. The two apical sites are occupied by one trisapa N atom(N1) and one nitrile N atom (N5) of another monodentate dicyanamide ( Fig. 1). Table. 2 shows the intermolecular hydrogen interactions between the uncoordinated N atoms of dicyanamide anions and the amine H atoms of trisapa, responsible of the construction of a three-dimensional network (Fig. 2). The Ni-N (trisapa) distances (2.100 (2)-2.196 (1) Å) are rather different, with values similar to the corresponding distances in the aliphatic amine nickel complexes (Cho et al., 2002;Brezina et al., 1999). The apical Ni-N (dicyanamide) distance(2.145 (1) Å) is slightly longer than the basal Ni-N(dicyanamide) distance(2.090 (2) Å). These distances in I are comparable to the corresponding ones in [Ni(tn) 2 {C 2 N 3 }](ClO 4 )(tn is trimethylenediamine, Li et al., 2002). In I, N-Ni-N cis angles range from 89.36 (7)° to 90.37 (6)° (basal-basal) and 84.32 (6)° to 95.61 (6)° (basal-apical), indicating that the distortion from an ideal octahedral geometry in I is not serious.

Experimental
A 4 ml ethanol solution of tris(3-aminopropyl)amine(0.10 mmol, 18.83 mg) and a 4 ml e thanol solution of nickel nitrate(0.10 mmol, 29.08 mg) were mixed and stirred for 5 min, the mixed solution was pale-blue. To the mixture was added a 2 ml aqueous solution of sodium dicyanamide (0.20 mmol, 17.81 mg). After stirred for another 5 min, the solution was filtered and the filtrate was slowly evaporated in air. After one week, blue block crystals of I were isolated in 34% yield. Anal: Calculated for C13H24N10Ni: C 41.18%, H 6.38%, N 36.95%. Found C 40.86%, H 6.47%, N 37.07%.

Refinement
One of the dicyanamide units is disordered in two halves, which were refined with restraints (both metric as in displacement factors). The corresponding occupation factors refined to 0.681/0.319 (19). The amine H atom were found from difference maps and refined freely with a final N-H range 0.80 (2) Å -0.92 (2) Å. Remaining H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms with C-H distances of 0.98 Å and U iso (H) = 1.2 × U(Host) .

Bis(dicyanamido-κN)[tris(3-aminopropyl)amine-κ 4 N]nickel(II)
Crystal data Hydrogen site location: inferred from neighbouring sites H atoms treated by a mixture of independent and constrained refinement w = 1/[σ 2 (F o 2 ) + (0.0475P) 2 + 0.0784P] where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max = 0.006 Δρ max = 0.38 e Å −3 Δρ min = −0.32 e Å −3 Special details Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.